Re: [PATCHv2] SVM: do not generate "external interrupt exit" if other exit is pending

["Roedel, Joerg" <Joerg.Roedel@amd.com>]

On Mon, Sep 20, 2010 at 04:15:32AM -0400, Gleb Natapov wrote:
> Nested SVM checks for external interrupt after injecting nested exception.
> In case there is external interrupt pending the code generates "external
> interrupt exit" and overwrites previous exit info. If previously injected
> exception already generated exit it will be lost.
> 
> Signed-off-by: Gleb Natapov <gleb@redhat.com>

Acked-by: Joerg Roedel <joerg.roedel@amd.com>

> ---
>  v1->v2
>   - Added comment
> 
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index 43f5558..ca778d5 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -1707,6 +1707,14 @@ static inline bool nested_svm_intr(struct vcpu_svm *svm)
>  	if (!(svm->vcpu.arch.hflags & HF_HIF_MASK))
>  		return false;
>  
> +	/*
> +	 * if vmexit was already requested (by intercepted exception
> +	 * for instance) do not overwrite it with "external interrupt"
> +	 * vmexit.
> +	 */
> +	if (svm->nested.exit_required)
> +		return false;
> +
>  	svm->vmcb->control.exit_code   = SVM_EXIT_INTR;
>  	svm->vmcb->control.exit_info_1 = 0;
>  	svm->vmcb->control.exit_info_2 = 0;
> --
> 			Gleb.
> 

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